Quite indirectly, boobs led to the invention of the stethoscope.

mentalfloss.com

Direct application of a doctor’s ear to a lady’s chest to listen to her heart was, shall we say, not ideal in the 19th century. Or any century, I suppose. Then a French doctor had an inspiration: he rolled up a sheet of paper into a tube and used that to listen to his patient’s heartbeat. Turns out it worked better than just using his ear. He refined the instrument, later called the stethoscope.